BACKGROUNDDespite their potential benefits to patients with kidney cancer, the adoption of partial nephrectomy and laparoscopy has been gradual and asymmetric. To clarify whether this trend reflects differences in kidney cancer patients or differences in surgeon practice styles, the authors compared the magnitude of surgeonâattributable variance in the use of partial nephrectomy and laparoscopic radical nephrectomy with that attributable to patient and tumor characteristics.METHODSBy using linked Surveillance, Epidemiology, and End ResultsâMedicare data, the authors identified a cohort of 5483 Medicare beneficiaries who underwent surgery for kidney cancer between 1997 and 2002. Two primary outcomes were defined: 1) the use of partial nephrectomy and (2) the use of laparoscopy among patients undergoing radical nephrectomy. By using multilevel models, surgeonâ and patientâlevel contributions to observed variations in the use of partial nephrectomy and laparoscopic radical nephrectomy were estimated.RESULTSOf the 5483 cases identified, 611 (11.1%) underwent partial nephrectomy (43 performed laparoscopically), and 4872 (88.9%) underwent radical nephrectomy (515 performed laparoscopically). After adjusting for patient demographics, comorbidity, tumor size, and surgeon volume, the surgeonâattributable variance was 18.1% for partial nephrectomy and 37.4% for laparoscopy. For both outcomes, the percentage of total variance attributable to surgeon factors was consistently higher than that attributable to patient characteristics.CONCLUSIONSFor many patients with kidney cancer, the surgery provided depends more on their surgeon's practice style than on the characteristics of the patient and his or her disease. Consequently, dismantling barriers to surgeon adoption of partial nephrectomy and laparoscopy is an important step toward improving the quality of care for patients with earlyâstage kidney cancer. Cancer 2008. Š 2008 American Cancer Society.